Spirane derivatives, their use and process for preparing same

ABSTRACT

Spirane derivatives, most of them are new, useful as odor-modifying ingredients for manufacturing perfumes and perfumed products, and as flavor-modifying ingredients for the manufacture of artificial flavors of for flavoring foodstuffs, animal feeds, beverages, pharmaceutical preparations and tobacco products. 
     Process for preparing said spirane derivatives.

CROSS REFERENCE TO RELATED APPLICATION

This application is a division of Ser. No. 625,452, filed Oct. 23, 1975,now U.S. Pat. No. 4,014,905 which in turn is a C-I-P of Ser. No.542,072, filed Jan. 17, 1975, now abandoned.

SUMMARY OF THE INVENTION

The invention relates to novel spirane derivatives of formula ##STR1##wherein the symbol R represents an acyl radical containing from 1 to 6carbon atoms and R² represents a hydrogen atom or methyl radical.

The invention further relates to the use of spirane derivatives offormula ##STR2## wherein the symbol R¹ represents a hydrogen atom or anacyl radical containing from 1 to 6 carbon atoms and R² represents ahydrogen atom or methyl radical, as odour- and flavour-modifyingingredients.

The invention also relates to 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-3-en-6-ol, 6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decane, 2,6,9,10,10-pentamethyl-6,7-epxoy-1-oxa-spiro[4.5]dec-3,6-diene, 2,6,9,10,10-pentamethyl-6,7-epoxy-1-oxa-spiro[4.5]dec-3-ene and 2,6,9,10,10-pentamethyl-6,7-epoxy-1-oxa-spiro[4.5]decane useful as intermediate compounds for the preparation ofcompounds (II).

The invention further relates to a perfume or a flavour-modifyingcomposition comprising as one of its active ingredients a spiranederivative of formula (II), as set forth hereinabove.

The invention finally relates to a process for preparing a spiranederivative of formula (II), said process comprising

(A) cyclizing a compound of formula ##STR3## to give a compound offormula ##STR4## epoxidizing the compound (IV) thus obtained to give acompound of formula ##STR5## reducing the above epoxide and, ifrequired, esterifying the obtained reduction product; or

(B) epoxidizing a compound of formula ##STR6## to give a compound offormula ##STR7## subjecting the above compound to a catalytichydrogenation to give a compound of formula ##STR8## reducing the aboveepoxide and, if required, esterifying the obtained reduction product; or

(c) reducing the compound (VI) described sub letter B to give a compoundof formula ##STR9## subjecting the above compound to a catalysthydrogenation and, if required, esterifying the obtained hydrogenationproduct; or

(D) epoxidizing and subsequently subjecting to an acidic treatment acompound of formula ##STR10## to give a compound of formula ##STR11##subjecting the above compound to a catalytic hydrogenation and ifrequired esterifying the obtained hydrogenation product.

BACKGROUND OF THE INVENTION

During the last decade, an increasing interest has been developed in theart of perfumery for materials possessing a woody-type odour. One of theconsequences of such an increase of interest consisted to promote adrastic shortage of naturally occurring materials traditionally used inthe art for the reconstitution of woody-type olfactive notes.

Patchouli oil is an example of this type of material. This essential oilis well known in the art for its typical woody and balsamic fragrance,at the same time spicy, sweet and herbaceous. The said essential oil ismoreover noteworthy for its particularly tenacious and powerful odour,and consequently is very broadly used in perfumery, particularly in fineperfumery, for the preparation of various compositions such as thosehaving an oriental, woody, "chypre" or "fougere" character for example.

It has been surprisingly found that it is now possible to faithfullyreproduce certain typical nuances of the odoriferous character ofnatural patchouli oil, by using spirane derivatives of formula (II).

2,6,10,10-Tetramethyl-1-oxa-spiro[4.5] decan-6-ol for example, when usedin a perfume or in a perfumed product, imparts thereto an elegant andharmonious woody and balsamic olfactive note similar to that obtained bythe use of patchouli oil itself.

It is known in the art that the fragrance of a given essential oilresults from the combination of the different odours of each individualconstituent of the said oil and can vary depending on the origin or onthe purity of the said natural essential oil. It is therefore very rareto find that a single compound can by itself totally reproduce the fullcharacter of an essential oil.

In certain cases however, patchouli oil can be advantageously replacedby the spiranic compounds (II) whenever it is desired to impart to aperfume or a perfumed product the woody and balsamic note typical of thesaid essential oil.

PREFERRED EMBODIMENTS OF THE INVENTION

We have surprisingly found that the compounds of formula (II) arecharacterized by their woody-type odour. Ester derivatives of formula(II) differ from the corresponding alcohols by a greater diffusenessassociated with an amber-like, balsamic, flowery and even herbaceousnote.

Spirane derivatives (II) are particularly useful in fine perfumery aswell as for the preparation of perfumed products such as soaps,detergents, household materials or cosmetic preparations for example.The compounds of formula (II), particularly2,6,9,10,10-pentamethyl-1-oxa-spiro[4.5]decan-6-yl acetate, can alsodevelop fruity sulfury organoleptic notes which are reminiscent of thecharacter developed by blackcurrent fruits.

When compounds (II) are used as ingredients for the preparation ofperfume compositions, the proportions used may vary within a wide rangeand are generally comprised between about 1 and 10% (parts by weight) ofthe said composition. Higher proportions, in some instances up to 50 oreven 80%, can also be used when compounds (II) are used as reinforcingagents in base perfume compositions. Lower proportions of the order ofabout 0.01% to 0.1% are used whenever the compounds of formula (II) areemployed to perfume products as soaps or detergents.

Owing to their particular organoleptic properties, compounds (II) canalso be used in the flavour industry as ingredients for the preparationof artificial flavours or for the aromatization of foodstuffs, animalfeeds, beverages, pharmaceutical preparations and tobacco products.

Depending on the nature of the products in which they are incorporated,compounds (II) can enhance or develop various gustative notes such aswoody, amber-like, earthy and in certain cases slightly flowery notes,or even notes reminiscent of that of cedar wood oil. Compounds (II) aretherefore particularly appreciated for the preparation of artificialflavors such as citrus fruits or even mushroom flavours wherein thewoody and earthy gustative note is often requested.

Compounds (II) can also advantageously be used for flavouring tobacco ortobacco products by imparting thereto a woody, amber-like and cedarwood-like note reminiscent of that of oriental tobaccos.

The woody and earthy note typical of certain compounds (II) is alsoappreciated for the aromatization of infusions or decoctions such astea, camomile or verbena for example.

The term "foodstuff" is here used broadly and includes also productssuch as coffee, tea or chocolate.

Depending on the nature of the flavoured material or on the organolepticeffects desired, the proportions used may very within a wide range. Whencompounds (II) are used as ingedients for flavouring foodstuffs orbeverages for example, interesting effects may be achieved by the use ofproportions comprised between about 0.01 and 20 ppm, based on the weightof the flavoured material. For the aromatization of tobacco or tobaccoproducts the proportions used are often comprised between 0.5 and 500ppm, preferably between 30 and 50 ppm.

When compounds (II) are used for the preparation of artificial flavours,they are generally used in proportions up to 20%, or even more, of theweight of the said composition.

In all cases, depending on the olfactive or gustative effects desired,smaller or higher proportions than those given above can also be used.

Most of the spirane derivatives of formula (II) which can be used inaccordance with the present invention are novel compounds, these latterones being represented by general formula (I).

In contradistinction, 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-olis a prior known compound, the preparation thereof being described inTetrahedron Letters 1969, 1955. It has to be noted however that theabove reference does not mention any organoleptic properties of saidalcohol nor does it suggest its use as perfuming or flavouringingredient.

Also new are the following spirane derivatives:2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-3-en-6-ol, 6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decane,2,6,9,10,10-pentamethyl-1-oxa-spiro[4.5]deca-3,6-diene,2,6,9,10,10-pentamethyl-6,7-epoxy-1-oxa-spiro[4.5]dec-3-ene and2,6,9,10,10-pentamethyl-6,7-epoxy-1-oxa-spiro[4.5] decane, useful asintermediate compounds in the preparation of spirane derivatives (II),in accordance with one of the objects of the present invention. Thefirst two of the above mentioned compound may be used, in a one stepprocess, as starting material for preparing2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol [R¹ = H in formula (II]as following:

2,6,10,10-tetramethyl-1-oxa-spiro4.5]dec-3-en-6-ol can be converted intothe desired alcohol by means of a catalytic haydrogenation; and

6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decane can be reduced bymeans of lithiumaluminium hydride to give the desired alcohol.

Due to the presence of several chirality centers in the molecule, namelyat carbon atoms 2, 5 and 6 of the spiro[4.5]decane skeleton, compounds(II) may exist in the form of at least one of the followingstereoisomers: ##STR12##

The C(6)--OR¹ bond can in fact possess a cis or trans configurationrelative to the C(5)--O bond of the heterocycle. This fact may bevisualized by means of formulae pairs (IIa) and (IIc), and (IIb) and(IId), respectively.

Moreover the methyl group at position 2 can also possess a cis or transconfiguration relative to, for example, the C(5) - C(6) bond of thecyclohexane ring. This isomerism can be visualized by means of formulaepairs (IIa) and (IIb), and (IIc) and (IId), respectively.

All the above stereoisomers can be isolated in their pure state by meansof a combination of several techniques such as fractional distillation,crystallisation and preparative vapour phase chromatography. A detaileddescription of the separation procedure applied to2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol and its correspondingacetate is given in Example 1.

For practical and economical reasons however, such a separationprocedure is generally not necessary. Compounds (II) are most commonlyused, in accordance with the present invention, as mixtures of"C(2)-epimers", i.e. as mixtures of stereoisomers (IIa) and (IIb) orstereoisomers (IIc) and (IId), respectively ##STR13## or even asmixtures comprising stereoisomers (IIa), (IIb), (IIc) and (IId).

Although it has been observed that in most of the applications the saidmixtures and their individual constituents can develop analogousorganoleptic effects, certain olfactive or gustative disparities havebeen observed.

Alcohol (IIA) for example (R¹ = H in formula IIA) develops aparticularly powerful woody and earthy odour whereas alcohol (IIB)possesses a more diffused woody note combined with a slightly flowerynuance. Ester derivatives, more precisely acetates (IIA) and (IIB) (R¹ =acetyl in formulae IIA and IIB) also differ one from the other, (IIB)presenting a more developed flowery note.

When acetate (IIA) is used as flavouring ingredient, it can becharacterized by its woody, amber-like and cedar-like taste, whereasacetate (IIB) develops a more diffused woody and slightly flowery taste,reminiscent in certain cases of that of ionones.

In accordance with one of the embodiments of the present invention,compounds (II) can be prepared starting from1-(2,6,6-trimethyl-cyclohex-1-enyl)-butan-1,3-diol when R² is a hydrogenatom or 1-(2,5,6,6-tetramethyl-cyclohex-1-enyl)-butan-1,3 diol when R²is methyl (III) as illustrated hereinbelow: ##STR14##

The first step of the above process, which formally consists in thecyclisation of (III) and the concomitant elimination of a molecule ofwater, can be effected in the presence of an acidic reagent. The alkalimetal salt of a polybasic acid such as sodium or potassiumhydrogenosulfate can be conveniently used to this end, as well as amineral or organic acid, e.g. sulfuric, phosphoric, hydrochloric orp-toluene-sulfonic acid. The said cyclisation can also be carried out inthe presence of an acidic diatomaceous earth.

In accordance with a preferred embodiment of the above process, the saidcyclisation can be effected by either

(a) directly mixing the diol (III) with the alkali metalhydrogenosulfate and subsequently heating the thus obtained mixture at atemperature comprised between about 50° and 150° C, preferably underreduced pressure, or

(b) dissolving compound (III) in an inert organic solvent such as anaromatic hydrocarbon, toluene or benzene e.g., or a halogenatedhydrocarbon, methylene chloride or chloroform e.g., and subsequentlyheating the above solution at the boiling temperature, in the presenceof alkali metal hydrogenosulfate.

The epoxidation of compound (IV) can be effected by means of an organicperacid, in accordance with known techniques. Suitable peracids areperformic, peracetic, trifluoroperacetic, perbenzoic, monochlorbenzoicor perphthalic acids.

The said epoxidation is moreover carried out in the presence of anorganic solvent such as chloroform, methylene chloride,trichloroethylene or dichloroethane e.g. Peracetic acid in methylenechloride is preferably used, in the presence of a buffering agent suchas sodium or potassium formate, acetate, propionate, butyrate, oxalate,citrate or tartrate e.g., sodium acetate being the preferred one.

Peracetic acid can also be prepared in situ from the action of hydrogenperoxide on acetic acid, in accordance with the method described in H.O.House, Modern Synthetic Reactions, 2nd ed. Benjamin Inc (1972), p. 293.

The reduction of compound (V) consists in the ring opening of the oxiranmoiety of the molecule to give the corresponding tertiary alcohol (R¹ =H in formula II). The said reduction can be performed in accordance withusual techniques, for example by means of an alkali metalaluminiumhydride such as lithiumaluminium hydrixe [see H.O. House,op.cit., p. 103].

The esterification in the thus obtained alcohol can be effected inaccordance with the known techniques, for example by means of an acylhalide, preferably an acyl chloride, in the presence of an organic basesuch as N,N-dimethyl-aniline e.g.

2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-6-yl acetate was prepared asindicated hereinabove from2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol and acetyl chloride.2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-6-yl formate on the contrarywas obtained by treating the above alcohol with formylimidazole,according to the method given in Liebigs Ann. Chem. 655, 95 (1962).

The diol of formula (III) used as starting material in the above processmay be obtained for example in accordance with the method described inGerman Patent Application No. 2,315,640.

In Accordance with another embodiment of the present invention,compounds (II) can be obtained from 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]deca-3,6-diene when R² is a hydrogen atomand 2,6,9,10,10-pentamethyl-1-oxa-spiro[4.5]decan-3,6-diene when R² ismethyl (VI) as described in the following reaction scheme: ##STR15##

The epoxidation of compound (VI) is effected as described above forcompound (IV).

The hydrogenation of both compounds (VII) and (VIII) is carried out inthe presence of a metal catalyst, according to the usual techniques. Thesaid hydrogenation may be effected in the presence of platinum oxide,palladium on charcoal or Raney-nickel e.g., and in the presence of aninert organic solvent such as an alcohol, methanol, ethanol orisopropanol e.g., or in the presence of an aliphatic or aromatichydrocarbon such as hexane, benzene or toluene e.g. The saidhydrogenation is preferably carried out by means of palladium oncharcoal, in ethanol.

The reduction of compound (VII) is effected as mentioned above forcompound (V), i.e. by means of an alkali metal aluminium hydride.

2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]deca-3,-diene or2,6,9,10,10-pentamethyl-1-oxa-spiro[4.5]deca-3,6-diene used as startingmaterials in the above process may be obtained from an acetylenicderivative of formula ##STR16## by treating the said derivative with anacidic dehydrating agent, according to the process given in Swiss Pat.No. 544,733.

In accordance with a further embodiment of the present inventioncompounds (II) can also be prepared from an unsaturated alicyclicalcohol of formula ##STR17## by epoxidizing and subsequently subjectingto an acidic treatment said compound (IX) to give a spirane derivativeof formula ##STR18## which is finally converted into compound (II) asmentioned hereinabove.

The epoxidation of 4-(2,6,6,-trimethyl-cyclohex-1-enyl)-but-cis3-ene-2-ol or 4-(2,5,6,6-tetramethyl-cyclohex-1-enyl)-but-cis 3-ene-2-ol(IX) is effected as given above for compound (IV). According to apreferred embodiment of the above process, the said epoxidation iseffected by means of peracetic acid in methylene chloride, in thepresence of sodium acetate.

The acidic treatment of the product resulting from the epoxidation ofcompound (IX) may be carried out by means of a mineral or organic acidsuch as hydrochloric, sulfuric, phosphoric, benzenesulfonic orp-toluenesulfonic acid e.g., or an acidic diatomaceous earth.

The said acidic treatment is moreover effected in the presence of aninert organic solvent, preferably that of the preceding reaction step,methylene chloride in the present case.

Compound (IX) used as starting material in the above process may beobtained from β-ionone, in accordance with the method given inJ.Org.Chem. 38, 1247 (1973).

The present invention will be better illustrated by the followingExamples wherein the temperatures are given in degrees centigrade andthe abbreviations have the meaning common in the art.

EXAMPLE 1 2,6,10,10-Tetramethyl-1-oxa-spiro[4,5]decan-6-ol

Method A:

(i) A mixture of 20 g (0.094 M) of1-(2,6,6-trimethylcyclohex-1-enyl)-butan-1,3-diol and 10 g of KHSO₄ washeated at 80°, under 0.1 Torr, in a reaction vessel equipped with alateral distillation column. After having collected the theoreticalamount of water the reaction mixture was heated to 100°-110° and 16.6 gof 2,6,10,10-tetramethyl-1-oxa-spiro [4.5]dec-6-ene (theaspirane) werethen distilled, b.p. 70°- 90°/0.1 Torr. An analytical sample waspurified by fractional distillation, b.p. 32°-33°/0.01 Torr.

Ir (neat): 2960, 1450, 1380, 1080, 1000 cm⁻¹

Nmr (ccl₄): 0.82 and 0.88 (6H, 2s); 1.18 (3H, d, J = 6 cps); 1.65 (3H,d, J = ca. 2 cps); 4.00 (1H, broad m); 5.18 (1H, broad m) δ ppm

Ms : m⁺ = 194; m/e = 179 (1), 138 (100), 123 (7), 109 (11), 96 (18), 82(27).

The cyclisation of 1-(2,6,6-trimethyl-cyclohex-1-enyl)-butane-1,3-diolcan also be carried out as indicated hereinbelow:

85 g (0.4 M) of the above diol in 250 ml of CHCl₃ were heated to refluxin the presence of 4.25 g of KHSO₄, in a reaction vessel equipped with awater-separator. Once the theoretical amount of water has beencollected, a new portion of 4.25 g of KHSO₄ was added and the reactionmixture was subjected to a fractional distillation to give 56 g (ca.72%) of theaspirane, b.p. 103°-105°/11 Torr.

(ii) 12 ml of a 40% solution of peracetic acid were added dropwise,under stirring, to a cold (0°-5°) mixture of 11.7 g (0.06 M) oftheaspirane -- see letter i --, 7.4 g of anhydrous sodium acetate and100 ml of methylene chloride. The reaction mixture was stirred for 5hours to 5°-10°, then kept overnight at 10° and finally filtered. Theclear liquid thus obtained was then washed with water, neutralized withsolid NaHCO₃, dried over Na₂ SO₄ and evaporated to give 11 g of a 70 :30 isomeric mixture of6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decane - isomers A andB - according to the vapour phase chromatography analysis.

Isomers A and B were separated on a larger scale (about 250 g) asfollows: 236 g of the epoxidation product of theaspirane were subjectedto a fractional distillation on a column filled with glass helices (1 =40 cm - φ = 2cm). 120.6 g of a fraction having b.p.51°-55°/0.1 Torr andcontaining 98% of isomer A were first collected, followed by 16.7 g of afraction having 70°-75°/0.1 Torr and containing 90% of isomer B. Thislatter product was finally purified by column chromatography (Silicagel-- eluant: CHCl₃) and subsequent crystallisation in aqueous ethanol. Thethus purified isomers present the following analytical data:

Isomer A:

B.p. 51°-52°/0.1 Torr

Ir (neat) : 2960, 1450, 1380, 1085, 1045, 1010, 970, 890 cm⁻¹

Nmr (ccl₄): 0.74 and 0.82 (6H, 2s); 1.20 (3H, s); 1.19 (3H, d, J =5cps); 1.85 (5H, m); 2.88 (1H, broad t); 4.03 (1H broad m) Γ ppm

Ms : m⁺ = 210 (24); m/e = 154 (61), 126 (66), 125 (50), 111 (32), 85(27), 69 (46), 55 (59), 43 (100), 41 (49).

Isomer B:

M.p. 40°

Ir (ccl₄) : 2980, 1450, 1380, 1360, 1090, 1010, 900 cm⁻¹

Nmr(ccl₄) : 0.75 (3H, s); 0.90 (3H, s); 1.21 (3H, s and 3H, d, J = 7cps); 2.82 (1H, broad t); 3.94 (1H, broad m) δ ppm

Ms : m⁺ = 210 (19); m/e = 154 (58), 126 (56), 125 (39), 111 (26), 70(27), 69 (38), 55 (53), 43 (100), 41 (41).

(iii) a solution of 3.74 g (0.018 M) of the epoxide obtained sub letterii -- isomer A -- in 25 ml of ether were added dropwise to a suspensionof 1 g of LiAlH₄ in 25 ml of ether, kept at 30°-35°. After the additionof the reactants, the obtained mixture was stirred for 3 hours to 35°,then 2 days at room temperature. After the addition of 25 ml of water,washing, drying, evaporation of the organic layer and fractionaldistillation of the obtained residue, 3.0 g (ca. 80%) of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol were isolated -- isomerA --.

The isomeric alcohol -- B -- was prepared as indicated hereinabove fromthe corresponding epoxide -- isomer B --.

Isomer A:

B.p. 58°-59°/0.5 Torr

Ir (neat) : 3490, 2940, 1480, 1380, 1080, 1005, 985 cm⁻¹

Nmr (ccl₄); 0.82 (3H, s); 1.10 (6H, 2s); 1.15 (3H, d); 1.80 (1H, s);4.00 (1H, broad m) δ ppm

Ms : m⁺ = 212 (4); m/e = 126 (89), 109 (29), 86 (70), 85 (100), 84 (51),69 (46), 55 (28), 43 (93), 41 (44).

Isomer A:

B.p. 38°/0.1 Torr

Ir (neat) : 3560, 2930, 1455, 1375, 1165, 1075, 965 cm⁻¹

Nmr (ccl₄): 0.89 (3H, s); 0.96 (3H, s); 1.17 (3H, s); 1.23 (3H, d, J = 7cps); 4.10 (1H, broad m) δ ppm

Ms : m⁺ = 212 (2); m/e = 126 (74), 109 (19), 86 (53), 85 (100), 84 (37),71 (20),69 (27), 43 (70), 41 (27).

Both isomers A and B are in fact mixtures of "C(2)-epimers" -- seepreceding part of the specification -- which have been individuallycharacterized as indicated hereinafter.

123 g of 2,6,10,10-tetramethyl-1-oxa-spiro [4.5]dec-6-ene (theaspirane)-- prepared sub letter i -- were subjected to a preparative vapour phasechromatography (CARBOWAX 20 M -- 4 m × φ 25 mm -- 140° to 175°) to givetwo portions of 37.5 g and 32.2 g, respectively. The above two fractionswere finally purified by means of a fractional distillation and gave31.5 g and 24.8 g of pure stereoisomers 1 and 2, respectively. ##STR19##NMR : 0.90 and 0.96 (6H, 2s); 1.28 (3H, d, J = 6 cps); 1.74 (3H, broads); 4.15 (1H, m); 5.26 (1H, broad s) δ ppm

Ms: m/e = 139 (10), 138 (100), 109 (13), 96 (21), 83 (14), 82 (33), 55(10), 43 (12), 41 (12). ##STR20## NMR: 0.87 and 1.00 (6H, 2s); 1.28 (3H,d, J = 6 cps); 1.73 (3H, broad s); 4.03 (1H, m), 5.41 (1H, broad t) δppm

Ms: m/e = 139 (10), 138 (100), 109 (14), 96 (23), 83 (15), 82 (31), 55(10), 43 (10), 41 (13).

30.3 g of theaspirane 1 were epoxidized as described sub letter ii toyield, after work up, 32 g of a 9 : 1 epimeric mixture of epoxides 3 and4. The above material was then subjected to a fractional distillation,using a column filled with glass helices (1 = 40 cm - φ2 mm), to give19.8 g of a fraction having b.p. 50°-55°/0.2 Torr and 2.2 g of afraction having b.p. 60° - 70°/0.2 Torr, respectively. The first of theabove two fractions was finally crystallized from aqueous ethanol andgave 4.2 g of pure 6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decane (stereoisomer 3).

1.5 g of the second fraction were subjected to a column chromatography(silicagel -- hexane/ethyl acetate) to yield 0.46 g of pure stereoisomer4, an oily colourless liquid. ##STR21## NMR : 0.79 and 0.89 (6H, 2s);1.26 (3H, d, J = 6 cps); 1.33 (3H, s); 3.07 (1H, broad t); 4.06 (1H, m)δ ppm

Ms : m⁺ = 210 (24); m/e = 154 (59), 126 (75), 125 (52), 111 (35), 70(33), 69 (42), 55 (62), 43 (100), 41 (57). ##STR22## NMR : 0.81 and 0.95(6H, 2s); 1.25 (3H, d, J = 6 cps); 1.40 (3H, s), 2.99 (1H, broad t);4.28 (1H, m) δ ppm

Ms : m⁺ = 210 (17); m/e = 154 (36), 126 (81), 125 (43), 111 (31), 70(37), 69 (44), 55 (52), 43 (100), 41 (49).

23.2 g of theaspirane 2 were epoxidized as described hereinabove toyield 24.5 g of a 3 : 2 epimeric mixture of epoxides 5 and 6. The abovemixture was then subjected twice to a fractional distillation, using acolumn filled with glass helices -- see above -- to give 11.9 g of anoily material having b.p. 53° - 55°/0.2 Torr, which was finally purifiedby means of a distillation on a spinning band column. There were thusobtained 1.3 g of pure stereoisomer 5.

10 g of a fraction having b.p. 65° - 70°/0.2 Torr, resulting from thefirst distillation, were crystallized twice from aqueous ethanol toyield 1.4 g of pure stereoisomer 6. ##STR23## NMR : 0.90 and 0.93 (6H,2s); 1.28 (3H, d, J = 6 cps); 1.31 (3H, s); 3.04 (1H, d, J = 2 cps);4.16 (I1H, m) δ ppm

Ms : m⁺ = 210 (26); m/e = 1.54 (64), 126 (45), 125 (34), 111 (27), 85(27), 69 (38), 55 (60), 43 (100), 41 (50). ##STR24## NMR : 0.76 and 0.90(6H, 2s); 1.30 (3H, d, J = 6 cps); 1.32 (3H, s); 2.98 (1H, broad s);3.90 (1H, m) δ ppm

Ms : m⁺ = 210 (17); m/e = 1.54 (70), 139 (33), 126 (56), 112 (36), 70(31), 69 (39), 55 (61), 43 (100), 41 (53).

Pure epoxides 3, 4, 5 and 6 were then converted into the correspondingalcohols by means of LiAlH₄ as given sub letter iii, to yield purestereoisomers 7, 8, 9 and 10, respectively. ##STR25## NMR : 0.87 and1.15 (6H, 2s); 1.19 (3H, s); 1.21 (i3H, d, J = 6 cps); 4.1 (1H, m) δ ppm

Ms : m⁺ = 212 (3); m/e = 126 (82), 86 (55), 85 (100), 84 (41), 71 (24),69 (33), 55 (24), 43 (86), 41 (36). ##STR26## NMR : 0.94 and 0.99 (6H,2s); 1.19 (3H, s); 1.25 (3H, d, J = 6 cps); 4.13 (i1H, m) δ ppm

Ms : m⁺ = 212 (2); m/e = 126 (78), 86 (55), 85 (100), 84 (40), 71 (21),70 (22), 69 (28), 43 (80), 41 (35). ##STR27## NMR : 0.9 and 1.06 (6H,2s); 1.14 (3H, s); 1.22 (3H, d, J = 6 cps); 4.05 (1H, m) δ ppm

Ms : m⁺ = 212 (3); m/e = 126 (77), 109 (25), 86 (49), 85 (100), 84 (39),69 (36), 55 (24), 43 (89), 41 (36). ##STR28## NMR : 0.92 and 0.99 (6H,2s); 1.25 (3H, d, J = 6 cps); 1.26 (3H, s); 4.12 (1H, m) δ ppm

Ms : m⁺ = 212 (1); m/e = 126 (75), 86 (51), 85 (100), 84 (38), 71 (21),69 (29), 55 (20), 43 (78), 41 (32).

The above pure alcohols were finally converted into the correspondingacetates, by means of acetyl chloride and N,N-dimethylaniline asdescribed in Example 3 hereinafter. Pure stereoisomers 11, 12, 13 and 14respectively were thus obtained. ##STR29## NMR : 0.88 and 1.08 (6H, 2s);1.23 (3H, d, J = 6 cps); 1.48 (3H,s); 1.99 (3H, s); 4.14 (1H, m) δ ppm

Ms : m⁺ = 254 (1); m/e = 194 (29), 138 (33), 126 (99), 125 (46), 85(27), 69 (59), 55 (30), 43 (100), 41 (41). ##STR30## NMR : 0.96 (6H, s);1.24 (3H, d, J = 6 cps); 1.55 (3H, s); 2.0 (3H, s); 4.24 (1H, m) δ ppm

Ms : m⁺ = 254 (1); m/e = 194 (27), 138 (25), 126 (100), 125 (50), 85(21), 69 (64), 55 (32), 43 (97), 41 (42). ##STR31## NMR : 0.90 and 0.99(6H, 2s); 1.27 (3H, d, J = 6 cps); 1.44 (3H, s); 2.0 (3H, s); 4.06 (1H,m) δ ppm

Ms : m⁺ = 254 (2); m/e 194 (31), 128 (27), 126 (88), 125 (35), 85 (29),69 (48), 55 (27), 43 (100), 41 (36). ##STR32## NMR : 0.94 and 1.0 (6H,2s); 1.25 (3H, d, J = 6 cps); 1.60 (3H, s); 2.01 (3H, s); 4.14 (1H, m) δppm

Ms : m⁺ = 254 (1); m/e 194 (28), 128 (23), 126 (98), 125 (39), 85 (31),69 (56), 55 (30), 43 (100), 41 (40).

All the above NMR spectra were carried out on a 90 MHz apparatus, inCDCl₃.

Method B:

(i) 22.7 g (0.12 M) of a 40% solution of peracetic acid were added to amixture of 19.2 g (0.1 M) of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]deca-3,6-diene, 12.3 g ofanhydrous sodium acetate and 100 ml of methylene chloride as indicatedabove -- see method A; letter ii -- . After the usual treatments ofwashing, drying and distillation, there were isolated 9.2 g of a producthaving b.p. 45°-47°/0.1 Torr and containing 90% of6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-3-ene in accordancewith the vapour phase chromatography analysis.

A new distillation of the above material finally gave 5.7 g of thedesired epoxide, b.p. 47°/0.1 Torr.

Ir (neat) : 2970, 1460, 1380, 1100, 1075, 910, 760 cm⁻¹

Nmr(ccl₄) : 0.70 (3H, s); 0.72 (3H, s); 0.86 (3H, s); 1.13 (3H, s); 1.23(3H, d, J = 7 cps); 1.27 (3H, d, J = 7 cps); 1.85 (2H, broad m); 2.92(1H, t); 4.90 (1H, m); 5.75 (2H, s); 5.78 (2H, s) δ ppm

Ms : m⁺ = 208 (1); m/e = 137 (39), 126 (68), 123 (46), 111 (22), 109(38), 95 (23), 55 (20), 43 (100), 41 (23).

(ii) 3.12 g of the above epoxide in 50 ml of ethanol were hydrogenatedin the presence of 312 mg of palladium on charcoal. After 340 ml ofhydrogen have been consumed, the reaction mixture was filtered,evaporated and finally subjected to a fractional distillation to give2.0 g (64%) of 6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decane --isomer A; see method A, letter ii -- , b.p. 51°/0.1 Torr.

(iii) 1.68 g of the above epoxide were subjected to a reduction carriedout by means of 455 mg of LiAlH₄ in accordance with the processdescribed in method A -- letter iii -- and gave 1.50 g (ca. 90%) of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol -- isomer A; see methodA, letter iii --.

2,6,10,10-tetramethyl-1-oxa-spiro[4.5]deca-3,6-diene used as startingmaterial in the above process was prepared from1-hydroxy-2,6,6-trimethyl-1-(3-hydroxy-but-1-yne-1-yl)-cyclohexane, bytreating this latter compound with a 30% aqueous solution of H₂ SO₄, inaccordance with the method described in Swiss Pat.No. 544733.

Ir (neat): 2990-2840, 1470, 1380, 1350, 1115, 1080, 980 cm⁻¹

Ms: m/e = 193, 136, 121, 94, 77, 53, 43, 41.

METHOD C

(i) 2.08 g (0.01 M) of6,7-epoxy-2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-3-ene - see methodB, letter i -- were reduced by means of 570 mg (0.015 M) of LiAlH₄ inaccordance with the above process. After the usual treatments ofwashing, drying and evaporation, the fractional distillation of theobtained residue gave 1.9 g (ca. 90%) of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-3-ene-6-ol, b.p. 80°-90°/9.1Torr.

Ir (ccl₄): 3620, 3490, 3070, 2930, 1455, 1370, 1190, 1080, 995, 935,870, 705 cm⁻¹

NMR(CCl₄): 0.80 (3H, s); 1.07 (6H, 2s); 1.20 and 1.22 (3H, 2d, J =7cps); 4.82 (1H, qd, J = 7cps); 5.82 (2l H, s) δ ppm

Ms: m⁺ = 210 (4); m/e = 149 (38), 126 (63), 125 (30), 123 (29), 109(50), 83 (22), 69 (29), 43 (100), 41 (21).

2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-3-ene-6-ol is a new compound,as well as its acetate derivative. Both compounds are characterized bytheir woody and balsamic odour, reminiscent in certain cases to that ofpatchouli. They can advantageously be used in perfumery or in theflavour industry as perfuming and/or flavouring ingredients.

2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-3-en-6-yl acetate possessesthe following analytical data:

Ir (neat): 1730 cm⁻¹

Nmr (cdcl₃): 0.83 (3H, s); 1.11 (3H, s); 1.25 (3H, d, J = 7 cps); 1.40(3H, s); 1.98 (3H,s); 4.88 (1H, m); 5.86 (2H, m) δ ppm

M⁺ = 252 (2); m/e = 209 (22), 127 (28), 126 (11), 123 (40), 109 (81), 83(12), 69 (29), 55 (11), 43 (100), 41 (18).

(ii) 53 mg of 2,6,10,10-tetramethyl-1-oxa-spiro 4.5]dec-3-ene-6-ol in 5ml of ethanol were subjected to a hydrogenation in the presence of 5 mgof palladium on charcoal. After the absorbtion of 5 ml of hydrogen, thereaction mixture was treated as described in method B -- letter ii -- togive 45 mg of a material containing 80% of the desired alcohol -- isomerA; see method A, letter iii -- and 20% of starting material according tothe vapour phase chromatography analysis.

Method D:

(i) 2.28 g (ca. 0.012 M) of a 40% solution of peracetic acid containing2% of sodium acetate were added dropwise to a cold -- 0° -- mixture of2.33 g (0.012 M) of4-(2,6,6-trimethyl-cyclohex-1-enyl)-but-cis-3-ene-2-ol, 1.73 g (0.018 M)of sodium acetate and 70 ml of methylene chloride. After the addition ofthe reactants, the reaction mixture was stirred for 15 hours at roomtemperature and finally filtered. The clear liquid thus obtained wasthen successively treated with 2 portions of a 10% aqueous solution ofNaHCO₃ and a saturated solution of NaCl, and then dried over Na₂ SO₄.After evaporation of the volatile parts, the thus obtained residue waspurified by means of a column chromatography (Silicagel -- eluant:cyclohexane/ethyl acetate 7 : 3) to give 0.53 g of starting material and1.76 g of an unidentified epoxy-derivative (ca. 90% yield).

(ii) The above epoxy-derivative was then treated with 50 ml of methylenechloride, in a presence of 0.07 g of p-toluenesulfonic acid and in anitrogen atmosphere. After having been stirred for 24 hours the reactionmixture was neutralized, washed, dried and evaporated as indicatedherein above -- see letter i -- and the distillation of the obtainedresidue gave 1.58 g (ca. 90%) of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-3-ene-6-ol.

(iii) 1.54 g (ca. 0.007 M) of the above alcohol were subjected to ahydrogenation in the presence of palladium on charcoal as indicatedabove -- see method C, letter ii -- 1.08 g (55%) of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol -- isomer A; see methodA, letter iii -- were thus isolated.

EXAMPLE 2 2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-6-yl formate

0.4 g (0.002 M) of 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol --isomer A; see Example 1 -- were intimately mixed with 0.5 g (0.005 M) offreshly sublimated formylimidazole and then kept for 2 days at roomtemperature. The reaction mixture was then extracted with ether and theorganic layer washed, dried, evaporated and finally subjected to afractional distillation to give 0.3 g of a product having b.p.70°-80°/0.5 Torr and containing 60% of the desired ester. An analyticalsample was purified by vapour phase chromatography.

Ir (neat): 2970, 1730, 1200, 1170, 1080 cm⁻¹

Nmr (cdcl₃): 0.88 (3H, s); 1.08 (3H, s); 1.22 (3H, d, J = 6 cps); 1.48(3H, broad s); 4.15 (1H, broad m); 8.12 (1H, s) δ ppm

Ms: (m + 1)⁺ = 241 (2); m/e = 194 (34), 138 (87), 126 (62), 125 (95), 82(30), 69 (100), 55 (42), 43 (61), 41 (56).

EXAMPLE 3 2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-6-yl acetate 5.9 g(0.079 M) of acetyl chloride were added over 30 minutes at 20° to amixture of 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol -- isomer A;see Example 1 -- and 10.9 g of N,N-dimethylaniline. After having beenkept for 2 days at room temperature the reaction mixture was heated toreflux during 3 hours, then cooled and treated with 50 ml of ether. Thereaction mixture was then filtered and the clear filtrate thus obtainedpoured onto crushed ice and finally acidified with a 10% aqueoussolution of H₂ SO₄. The organic layer was then washed with NaHCO₃ inwater, dried, evaporated and subjected to a fractional distillation togive 2.5 g of a product having b.p. 90°-100°/0.1 Torr. Aftercrystallisation in aqueous ethanol 1.9 g (75%) of the desired ester wereisolated -- isomer A --.

The isomeric acetate B was obtained from the corresponding alcohol --isomer B; see Example 1 -- as indicated hereinabove.

Isomer A:

M.p. 55°-56°

Ir (chcl₃) 2950, 1730, 1360, 1240, 1160, 1070 cm⁻¹

Nmr (cdcl₃): 0.87 (3H, s); 1.07 (3H, s); 1.22 (3H, d, J = 6 cps); 1.44(3H, s); 1.95 (3H, s); 4.10 (1H, broad m) δ ppm

Ms: (m + 1)⁺ = 255 (2); m/e = 194 (29), 138 (26), 126 (100), 125 (38),85 (24), 69 (45), 55 (22), 43 (85), 41 (28).

Isomer B:

M.p. 46°

Ir (chcl₃): 2980, 1720, 1375, 1255, 1090, 905 cm⁻¹

Nmr (cdcl₃): 0.93 (3H, s); 0.98 (3H, s); 1.24 (3H, d, J = 7 cps); 1.57(3H, s); 1.98 (3H, s); 4.14 (1H, broad m) δ ppm

Ms: m⁺ = 254 (1); m/e = 194 (32), 138 (30), 126 (97), 125 (53), 85 (29),69 (67), 55 (31), 43 (100), 41 (41).

EXAMPLE 4 2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-6-yl propionate

2.17 g (0.01 M) of 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol --isomer A; see Example 1 -- were treated with a mixture of 12.1 g (0.10M) of N,N-dimethylaniline and 4.62 g (0.05 M) of propionyl chloride asindicated in Example 3 to give 1.7 g (63%) of the desired ester, b.p.100°-110°/0.5 Torr.

Ir (neat) : 2950, 1730, 1460, 1370, 1190, 1160, 1070, 1010 cm⁻¹

Nmr (cdcl₃): 0.87 (3H, s); 1.07 (3H, s and 3H, t, J = 7 cps); 1.21 (3H,d, J = 6 cps); 1.43 (3H, s); 4.12 (1H, broad m) δ ppm

Ms: (m + 1)⁺ = 269 (2); m/e = 194 (36), 138 (28), 126 (100), 125 (38),85 (25), 69 (46), 57 (35), 43 (52), 41 (29).

EXAMPLE 5 2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-6-yl butyrate

2.12 g (0.01 M) of 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol --isomer A; see Example 1 -- were treated with a mixture of 12.1 g (0.1 M)of N,N-dimethyl-aniline and 5.3 g (0.05 M) of butyryl chloride asindicated in Example 3 -- except heating at 100° for 3 hours -- to give1.6 g (57 %) of the desired ester, b.p. 120°/0.5 Torr.

Ir (neat) : 2960, 1720, 1450, 1370. 1180, 1150, 1070, 1000 cm⁻¹

Nmr (cdcl₃): 0.88 (3H, s); 1.08 (3H, s); 1.10 (3H, t); 1.22 (3H, d, J =6 cps); 1.45 (3H, s); 4.12 (1H, broad m) δ ppm

ms: (M + 1)⁺ = 283 (2); m/e = 211 (24), 194 (41), 138 (30), 126 (100),125 (40), 71 (29), 69 (48), 43 (76), 41 (36).

EXAMPLE 6 2,6,10,10-Tetramethyl-1-oxa-spiro[4.5]dec-6-yl isobutyrate

2.12 g (0.01 M) of 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol --isomer A; see Example 1 -- were treated with a mixture of 12.1 g (0.1 M)of N,N-dimethylaniline and 5.3 g (0.05 M) pf isobutyryl chloride asindicated in Example 5 to give 0.3 g (ca. 11%) of the desired ester,b.p. 110°/0.5 Torr.

Ir (neat) :2960, 1725, 1470, 1380, 1290, 1150, 1080, 1010 cm⁻¹

Nmr (cdcl₃): 0.88 (3H, s); 1.09 (3H s); 1.17 and 1.19 (6H, 2s); 1.20(3H, d, J = 6 cps); 1.43 (3H, s) 4.13 (1H, broad m) δ ppm

Ms : (m + 1)³⁰ 283 (2); m/e = 194 (42), 138 (33), 126 (94), 125 (44), 71(27), 69 (51), 55 (28), 43 (100), 41 (43).

EXAMPLE 7

A black tea infusion possessing a relatively bland taste was preparedfrom 6 g of commercial black tea leaves and 1 liter of boiling water.After few minutes the above infusion was poured into small cups, at arate of 30 ml per cup. "Test" samples were then prepared by adding toeach cup of hot tea 0.06 ml of a 0.001% solution of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol-isomer A; see Example 1-- in 95% ethyl alcohol. A "control" sample was obtained by adding 95%ethyl alcohol to the hot tea, in the same proportions.

"Test" and "control" samples were then subjected to the evaluation of apanel of flavour experts who unanimously declared that the "test"samples possessed a particularly pleasant woody character when comparedto the unflavoured material.

Analogous organoleptic effects were obtained, however less pronounced,by replacing the above alcohol by its B isomer -- see Example 1 --.Similar effects were observed by using in the same proportion2,6,9,10,10-pentamethyl-1-oxa-spiro[4.5]decan-6-ol instead of the abovementioned tetramethyl derivative.

EXAMPLE 8

A commercial mushroom soup was flavoured with2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol -- isomer A; seeExample 1 -- in the proportions of 0.03 mg of the above alcohol per kgof foodstuff: "test" sample. The thus flavoured soup was then comparedto an unflavoured material by a panel of experts who declared that the"tst" sample possessed a well distinct woody and earthy note.

The above aromatization procedure was then repeated, by replacing2,6,10,10-tetramethyl-1-oxa-spiro [4.5]decan-6-ol by its correspondingacetate -- isomer A; see Example 3 --. In that case it was found thatthe flavoured foodstuff possessed an improved woody character togetherwith a pleasant cedar-like nuance.

EXAMPLE 9

To 1 liter of an acidulous sugar syrup (prepared by diluting 650 g ofsucrose and 10 ml of a 50% aqueous solution of citric acid in 1000 ml ofwater), flavoured with lemon oil in the proportion of 30 g of the saidoil per 100 l of syrup, there was added 1 ml of a 0.1% ethanolicsolution of 2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-6-yl acetate --isomer A; see Example 3 -- to give the "test" sample. The thus flavouredsyrup was then compared to a material containing 95% ethyl alcohol inthe proportions given hereinabove ("control" sample) by a panel ofexperts who declared that the "test" beverage possessed a more markedand more pleasant woody note.

By replacing the above acetate by its B isomer -- see Example 3 --analogous effects were achieved. The observed gustative note however wasmore diffused and possessed moreover a flowery nuance.

By replacing, in the above aromatization procedure,2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-6-yl acetate by thecorresponding formate or propionate -- see Example 2 and 4 respectively-- analogous effects were observed. In this case however higherproportions were used (about ten times more).

EXAMPLE 10

100 mg of a 0.1% ethanolic solution of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]decan-6-ol -- isomer A; seeExample 1 -- were sprayed onto 100 g of an "american blend" tobaccomixture. The tobacco thus flavoured was used for the manufacture of"test" cigarettes, the smoke of which was then subjected to organolepticevaluation by comparison with unflavoured "control⃡ cigarettes. Thetobacco used to prepare the "control" was preliminary treated with acorresponding amount of 95% ethyl alcohol.

A panel of flavour experts defined the taste of the smoke of the "test"cigarettes as possessing a typical woody and earthy character.

By replacing, in the above flavouring procedure, the above alcohol bythe corresponding acetate -- isomer A; see Example 3 -- in theproportions of 0.3 g of 1% ethanolic solution per 100 g of tobacco, itwas declared that the "test" cigarettes possessed a particularlypleasant woody and amber-like character, reminiscent at the same time ofthat of cedar wood.

By replacing the above acetate by its B isomer -- see Example 3 --analogous effects were observed. The thus obtained woody and amber-likenote was however more diffused and presented moreover a flowery nuance.

EXAMPLE 11

A base perfume composition for shampooings was prepared by admixing thefollowing ingredients (parts by weight):

    ______________________________________                                        Phenylethyl alcohol                                                                              130                                                        Ethylenebrassylate 100                                                        Aspic oil 10%*     80                                                         Synthetic geraniol 80                                                         Synthetic bergamot 80                                                         Linalyl acetate    60                                                         Synthetic geranium 60                                                         Oak moss absolute 10%*                                                                           60                                                         Patchouli oil      40                                                         Labdanum resinoid 10%*                                                                           40                                                         p-ter-Butyl-cyclohexyl acetate                                                                   30                                                         Musk ketone        30                                                         Coumarin           30                                                         Terpineol          30                                                         Methyl-isoeugenol  30                                                         Rosemary oil       20                                                         Galbanum oil 10%*  20                                                         Isocamphyl-cyclohexanol                                                                          20                                                         Synthetic civet 10% *                                                                            20                                                         Lavandin absolute, discolourized                                                                 10                                                         Synthetic neroli   15                                                         Lilial ® , L. Givaudan & Cie SA                                                              10                                                         Myrtle oil         5                                                          Total              1000                                                       ______________________________________                                         *in diethyl phthalate                                                    

The above base composition possesses an intense and typical woody note,due to the presence of patchouli oil.

By replacing in the above base the 40 parts of patchouli oil by 80 partsof 2,6,10,10-tetramethyl-1-oxa-spiro-[4.5]decan-6-ol, there was obtaineda new perfume composition similar to the above base, the woody andbalsamic notes thereof being more pronounced.

EXAMPLE 12

A base perfume composition for an after-shave lotion was prepared byadmixing the following ingredients (parts by weight):

    ______________________________________                                        Synthetic bergamot 120                                                        p-ter-Butyl-cyclohexyl acetate                                                                   100                                                        Methyl-octylacetic aldehyde 10%*                                                                 80                                                         Synthetic jasmine  60                                                         Lemon oil          60                                                         Florida orange oil 50                                                         "Mousse d'arbre" concrete 10%*                                                                   50                                                         Lavandin absolute  40                                                         Clove oil of Madagascar                                                                          40                                                         Galbanum resinoid  40                                                         Synthetic neroli   40                                                         Undecylic aldehyde 10%*                                                                          20                                                         α-Phenylethyl acetate                                                                      20                                                         Cananga oil        20                                                         Methyl-ionone      20                                                         Musk ambrette      20                                                         2,4-Dimethyl-cyclohex-3-enyl-                                                 carbaldehyde 10%*  20                                                         Total              1000                                                       ______________________________________                                         *in diethyl phthalate                                                    

By adding to 80 g of the above base 10 g of2,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-6-yl acetate -- isomer A; seeExample 3 -- there was obtained a new perfume composition possessing aparticularly elegant woody character, reminiscent of that of vetiver.

By replacing in the above composition the above acetate by its B isomer-- see Example 3 -- a similar effect was observed. The thus obtainedcomposition possessed however a more diffused woody note together with aflowery tonality.

EXAMPLE 13

A base perfume composition having a woody odour was prepared by admixingthe following ingredients (parts by weight):

    ______________________________________                                        Synthetic bergamot                                                                              300                                                         Vetyveryl acetate 150                                                         Florida cedar wood oil                                                                          120                                                         Methyl 2-pentyl-3-oxa-cyclo-                                                  pentyl-acetate    120                                                         Oak moss absolute 10%*                                                                          120                                                         Isocamphyl cyclohexanol                                                                         90                                                          Total             900                                                         ______________________________________                                         *in diethyl phthalate                                                    

The above base possesses a typical woody character, mainly due to thepresence of vetyveryl acetate and cedar wood oil. It is particularlysuitable for the preparation of various perfume compositions, forexample for those having a "masculine" tonality.

By adding to 90 g of the above base 10 g of7,6,10,10-tetramethyl-1-oxa-spiro[4.5]dec-6-yl acetate -- isomer A; seeExample 3 -- the woody character of the said base was improved and thethus obtained composition presented a more elegant and more harmoniousoverall effect.

EXAMPLE 14 2,6.9,10,10-Pentamethyl-1-oxa-spira [4.5] decan-6-ol

(a) 12ml of a 40% solution of paracetic acid were added within 1h understirring to a mixture cooled at 0°-5° of 12.4 g (0.06M) of2,6,9,10,10-pentamethyl-1-oxa-spira [4.5] deca-3,6-diene, 7.4 g ofanhydrous sodium acetate and 100 ml CH₂ Cl₂. The whole is kept understirring during 5h at 5°-10°, then overnight at 10° and the mixture wasfiltered. The clear filtrate, washed with H₂ O, neutralized by means ofNaHCO₃ and dried over Na₂ SO₄, was evaporated to give 10 g of2,6,9,10,10-pentamethyl-6,7-epoxy-1-oxa-spiro [4.5] dec-3-ene. A gaschromatography purified sample of this epoxide had the followingspectral data:

Ir(film): 3100, 3000, 2960, 2900, 2870, 1445, 1090, 1050, 1040, 1000,950, 905 cm⁻¹

M⁺ = 222 (7); m/e: 140 (45), 123 (100), 109 (59), 43 (85).

(b) 8 g of the product obtained sub letter a) above were dissolved in100 ml of ethanol and catalytically hydrogenated in the presence of 800mg of 5% palladium on charcoal. On evaporation and fractionaldistillation, 8 g of 2,6,8,10,10-pentamethyl-6,7-epoxy-1-oxa-spiro [4.5]decane were obtained. An analytical sample was purified by gaschromatography and showed the following characteristics:

Ir(film) 1460, 1380, 1090, 1020 cm⁻¹ ;

Ms: m⁺ = 224 (8); m/e: 139 (66), 125 (92), 43 (100), 41 (65).

(c) 4.0 g (0.018M) of the above obtained compound (see letter (b)) weredissolved in 25 ml of ether and the solution was added at 30°-35° to asuspension of 1 g of LiAlH₄ in 25 ml ether. Once the addition is over,the mixture is stirred during 3h at room temperature, then 48h at 20°,whereupon water was added thereto. After separation, washing and dryingof the organic phase over MgSO₄, followed by distillation of theobtained residue, there were isolated 3.0 g of2,6,9,10,10-pentamethyl-1-oxa-spiro [4.5] decan-6-ol, the spectral dataof which were the following:

Ir(film) 3520, 2980, 2950, 2890, 1455, 1380, 1375, 1140, 1085, 1010, 940cm⁻¹ ;

This product was isolated under the form of a mixture of two isomers (Aand B) which could be separated by gas chromatography:

Isomer A

Nmr (cdcl₃ ; 90MHz): 0.91(3H,s); 0.98 (3H,s); 0.89(3H,dJ = 5 cps);1.22(3H,d,J = 6 cps); 1.27(3H,s); 1.53(1H,s); 4.13(1H,m) δppm M⁺ = 226(<1); m/e: 126(84),

Ms: 125(57), 85(100), 69(46).

isomer B

Nmr (cdcl₃ ; 90MHz): 0.82(3H,s); 0.92(3H,s); 0.84(3H,d,J = 5 cps);1.22(3H,d,J = 6 cps); 1.35(3H,s); 1.53(1H,s); 4.11(1H,m) δppm

Ms: m⁺ = 226 (<1); m/e: 126(88), 125(86), 85(94), 69(69), 43(100).

2,6,9,10,10-Pentamethyl-1-oxa-spiro [4.5] deca-3,6-diene, used asstarting material in step (a) hereinabove could be prepared from1-hydroxy-2,5,6,6-tetramethyl-1-(3-hydroxybut-1-yn-1-yl)-cyclohexane bytreating said carbinol with a 30% aqueous solution of H₂ SO₄ asindicated in Swiss Pat. No. 544,733. The compound possessed moreoververy interesting organoleptic properties and consequently couldadvantageously be used as flavouring and perfuming agents. It develops avery powerful natural fruity, minty character reminiscent of certainperfuming notes typical of black-currant fruits.

EXAMPLE 15

In accordance with the procedure described in Example 3, it was providedto the preparation of 2,6,9,10,10-pentamethyl-1-oxa-spiro [4.5] dec-6-ylacetate. The spectral data of the obtained ester were the following:

Ir(film): 1740, 1465, 1370, 1255, 1095, 1025 cm⁻¹ ;

Nmr (cdcl₃ 90 MHz): 0.91(3H,s); 0.98(3H,s); 1.20 (3H,d,J = 6 cps);1.47(3H,s); 1.98(3H,s); 4.09(1H,m) δppm

Ms: m/e: 138(88), 137(51), 125(100), 69(81), 43(66).

EXAMPLE 16

A base perfume composition for shampoos was prepared by admixing thefollowing ingredients (parts by weight):

    ______________________________________                                        Phenylethyl alcohol     170                                                   Ethylenebrassylate 10%* 100                                                   Aspic oil               80                                                    Synthetic geraniol      80                                                    Synthetic bergamont     80                                                    Lynalyl acetate         60                                                    Synthetic geranium      60                                                    Absolu oak-moss 10%*    60                                                    Labdanum resinoid 10%*  40                                                    p-ter-Butyl-cyclohexyl acetate                                                                        30                                                    Musk ketone             30                                                    Coumarin                30                                                    Terpineol               30                                                    Methyl-isoeugenol       30                                                    Rosmarin oil            20                                                    Galbanum oil 10%*       20                                                    Isocamphyl-cyclohexanol 20                                                    Synthetic Civet 10%*    20                                                    Synthetic neroli        15                                                    Lavandin absolute colorless                                                                           10                                                    p-ter-Butyl-α-methyl-dihydrocinnamic                                    aldehyde                10                                                    Myrtle oil              5                                                     Total                   1000                                                  ______________________________________                                         *in diethyl phthalate                                                    

By adding to 95 g of the above composition, 5g of2,6,8.10,10-pentamethyl-1-oxa-spiro [4.5] decan-6-ol, a novelcomposition resulted with an improved pleasant woody, vetyver-like odourcharacter.

What we claim is:
 1. A process for improving, enhancing or modifying theorganoleptic properties of tobacco products which comprises addingthereto a spirane derivative of formula ##STR33## wherein the symbol R¹repersents a hydrogen atom or an acyl radical containing from 1 to 6carbon atoms and R² represents a hydrogen atom or a methyl radical.
 2. Atobacco product comprising as a flavour-modifying ingredient a spiranederivative of formula (II), as set forth in claim 1.